The present invention refers to aerogenerators for capturing wind energy and transforming it into electrical, mechanical or other type of energy.
In the aerogenerators to which the present invention refers, there are three problematical areas which have been the object of different technical proposals.
In the first place optimalisation of the use of wind power has led to proposals for aerogenerators in which the rotor blades have appropriate shapes to approximate to the maximum potential levels of exploitation of wind energy described in Betz""s theory, avoiding especially the limitative factors due to turbulence, and also to proposals for aerogenerators with variable rotor orientation which can be adjusted according to wind direction.
Secondly, different types of solutions are also known for confronting mechanical problems arising especially in aerogenerators with rotors having blades of great size and, in fact, today there are aerogenerators with rotor diameters of between 60 and 80 m, which operate satisfactorily.
Thirdly, the problems of converting wind energy into, especially, electrical energy have been the object of different technical proposals.
In spite of the fact that the known technology has achieved aerogenerators which, contrary to what was thought originally, have achieved acceptable levels of profitability in producing electrical energy, such aerogenerators, especially those of great size, involve very complex installations and require very high investment which limits their application.
The present invention is intended to resolve these drawbacks. While the different mentioned proposals have acted basically upon one of the determining factors of energy production, that is, the sweeping area of the rotor blades, resolving the problems arising from the use of greater rotor diameters to obtain greater power, the present invention proposes to act upon the other factor; wind sped, by accelerating its flow.
This in also the purpose of the devices described in FR 1 035 426 and FR 2 450 252. In particular FR 2 450 252 describes an eolian device having a rotating helix or turbine inside one wind-channeling conduit.
According to the first object of the invention, an eolian tower is provided with rotor blades which turn on a horizontal axis connected to devices for converting wind energy into another type of energy, which incorporates a wind-channeling conduit with a narrowing in its central part, where a rotor of the known type is situated which sweeps a circular area in the central part of the said narrowing. This structure causes an acceleration of wind flow which, with rotors of small diameter, allows result to be achieved which are similar to those obtained at the present time with rotors of much greater diameter. For its part, the incorporation of the conduit considerably simplifies the problem arising from the use of rotors of great diameter both in their mechanical aspect and in the aspects relating to the devices for converting into electrical or other types of energy.
The term xe2x80x9ceolian towerxe2x80x9d is used to denominate the object of the present invention in this description, instead of aerogenerator or other names used for any device for transforming wind energy into another type of energy, because, although they have similar purposes, the incorporation of the above-mentioned conduit confers upon it a very different outer appearance. Hovewer we will use the term aerogenerator in the claims to avoid any misunderstanding with the meaning of xe2x80x9ceolian towerxe2x80x9d.
According to the second object of the invention, an eolian tower in provided which incorporates a wind-channeling conduit with a narrowing in the form of a circular crown in which a rotor is situated whose blades are configured in a shape appropriate to act on a sweeping area in the form of a circular crown.
According to the first and second object of the invention, the third object of the invention refers to the additional inclusion of closing means in the eolian towers for closing the intake mouth of the wind-channeling conduit and means for regulating the speed at which the wind enters in order to provide the rotors associated with the corresponding means of energy generation with a wind flow of optimal speed for transforming the wind energy into another type of energy.